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            <h2 class="title" style="clear: both"><a id="am_sync"></a>Flushing the database cache</h2>
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      <p>
        The <a href="../api_reference/C/dbsync.html" class="olink">DB-&gt;sync()</a> method flushes all modified records from the
        database cache to disk.
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        <span class="bold"><strong>It is important to understand that
            flushing cached information to disk only minimizes the
            window of opportunity for corrupted data, it does not
            eliminate the possibility.</strong></span>
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        While unlikely, it is possible for database corruption to
        happen if a system or application crash occurs while writing
        data to the database. To ensure that database corruption never
        occurs, applications must either:
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            Use transactions and logging with automatic
            recovery.
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            Use logging and application-specific
            recovery.
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          <li>
            Edit a copy of the database, and, once all
            applications using the database have successfully called
            <a href="../api_reference/C/dbclose.html" class="olink">DB-&gt;close()</a>, use system operations (for example, the POSIX
            rename system call) to atomically replace the original
            database with the updated copy.
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